Two cycle internal combustion motor



E. J. KNOX TWO-CYCLE INTERNAL COMBUSTION MOTOR Filed Nov. 2, 1936 Jan. 4, 1938.

Patented Jan. 4, 1938 UNITED STATES PATENT OFFICE TWO CYCLE INTERNAL COMBUSTION MOTOR 3 Claims.

vMy invention relates to improvements in two stroke internal combustion motors, in which intake and exhaust ports are opened and closed by the reciprocation of the piston in the cylinder; and the objects of my improvement are, first, to provide a greater working stroke, second, to distribute the heat of combustion over a greater radiating surface, third, to aid the scavenging of the burnt gases, fourth, to provide turbulence in the fresh charge.

I attain these objects by mechanism illustrated in the accompanying drawing, in which,

Figure 1 is an outside view of the motor.

Figure 2 is a vertical cross section of the cyl,-

' inder through the center on the line 2 2 of Figure 1.

Figure 3 is a horizontal cross section of the cylinder on the line 3 3 of Figure 2, taken at the center of the exhaust ports, and the piston at the center of the intake passages.

Figure 4 is a vertical section of the cylinder with the piston at upper dead center.

Figure 5 is a horizontal section on the line 5 5 of Figure 4.

Similar numbers refer to throughout the several views.

The complete motor consists of a crankcase I, in which a mixture of air and gasoline, or other hydrocarbon fuel is compressed prior to introducing it into the combustion chamber, a cylinder 5, connected to the crankcase and a crankshaft 2; hung in bearings l3 |3, a connecting rod 3 fastened to the throw of the crankshaft, being free to turn and imparting a reciprocating motion to the piston 4 fastened to the other end. The cylinder has a smooth bore to accommodate the piston, and passages 8 8 on the outside of the cylinder extending down from the top of the combustion chamber below the exhaust ports, these passages opening to the bore at the top and below the exhaust ports. Passages 9 9, open into the crankcase at the bottom and extend upward far enough to connect with Vpassages 6 6 in the piston, when it is on bottom dead center, passages 8 8 then connect with passages 6 6, and form continuous passages, for a fresh charge compressed in the crankcase to pass into the combustion chamber. The fresh charge entering at the top of the cylinder from opposite sides, forms a blanket over the burnt gases and forces them down and out the exhaust ports 1, and the manifold I4, substantially without mixing the spent gases with fresh charge. The piston passages 6 6 register with the lower openings of the upper passages 8 8 at one half stroke similar parts (Cl. 12S-73) and the gas compressed and trapped in the piston chambers during the compression stroke rush into the chambers 8 8 and ignite, boosting the pressure in the cylinder and maintaining a longer power stroke. The exhaust ports 1, extending 5 around the cylinder allow the exhaust gases to escape faster, therefore they may be placed lower down on the cylinder, giving a longer power stroke. The charge being partially compressed in the passages 8 8, partially in the piston 10 chambers 6 6, and partially in the combustion chamber, creates a good deal of turbulence in the charge, assists in rapid flame propagation, and distributes the heat of combustion over a larger area of the cylinder.

The cylinder may be jacketed for water cooling or finned for air cooling. The Vfresh charge may be admitted to the crankcase through ports l0, that are opened by the piston when at the top of the stroke, or through any other device. Means 20 of mixing a hydrocarbon fuel with air in the proper proportion to obtain an explosive mixture, and means of igniting the mixture when compressed in the cylinder by spark plugs Il ll, and means of lubricating the working parts are 25 provided. The motor may be made with a plurality of cylinders without changing the principles of this invention. The piston will be provided with packing rings, at the top, and bottom, and between the openings of the passages 30 6 6, the rings so spaced that at the end of the stroke the outer edge of the top and bottom rings will pass slightly by the ends of the bore, the combustion chamber being larger than the bore.

I am aware that prior to my invention, motors have been made, using ports uncovered by the movement of the piston, I therefore do not claim such a combination broadly; but

I claim:

l. The combination, in a two cycle internal combustion engine, of a cylinder, a piston reciprocating therein, double opposed longitudinal passages, opening into the cylinder only at the top, and below the exhaust ports, and similar passages 45 farther down the cylinder opening into the bore, and continuing into the crankcase, the middle ends being adapted to be opened and closed by the reciprocation of the piston, with a piston having double opposed chambers located on its sides, with openings located between bottom and top rings, adapted to be opened and closed by the reciprocation of the piston, and registering at bottom dead center with the cylinder passage openings to form continuous passages from the crankcase to the top of the cylinder, and the bottom Vopenings of the piston chambers registering with and other similar passages, opening into the boreV farther down, and the lower ends being in open communication with the crankcase, the middle openings being adapted to. be opened and closed by the reciprocation of the piston, a piston with double opposed combustion chambers with openings adapted to register with the cylinder passageV openings at bottom dead center, forming continuous passages from the crankcase to the top of the cylinder, through the piston chambers, and the lower openings of the piston chambers registering with the lower openings of. the upper cylinder passages at about one half power stroke, and means of igniting the charge in the upper passages, substantially as illustrated and described.

3. VIn a gas engine,ja cylinder, a piston, the

Vcombination of longitudinal passages in the cylinder external to the bore and communicating with it, at the top, and below the exhaust ports, and other similar passages loweridown communieating with the crankcase and the middle openings being adapted to be opened and closed by the reciprccation of the piston, the piston having double opposed combustion chambers located on its sides with openings that register with the openings of the cylinder passages at bottom dead Vcenter, and the lower openings of the piston chambers registering with the lower openings of the upper cylinder passages at about one half stroke, and means of igniting the charge in the upper cylinder passages, with a plurality of. packing rings'located above, below and between the piston chamber openings, the outer edges of the top and bottom rings located so asY to pass slightly beyond the ends of the bore.

ELMER JAMES KNOX. 

